Lung disease mortality in the United States: the National Longitudinal Mortality Study.

SETTING: The National Longitudinal Mortality Study (NLMS) offers the advantage of assessing mortality in a representative population of the United States. OBJECTIVE: To evaluate health disparities associated with lung cancer and chronic obstructive pulmonary disease (COPD) mortality in the United States and whether these associations are similar between these outcomes. DESIGN: The NLMS is a prospective study. Data from NLMS cohort years 1985, 1992, 1993, 1995 and 1996 were included, representing nearly 1.5 million person-years. Lung cancer and COPD mortality relative risks (RRs) from Cox regression analysis, including residential characteristics, marital status, education, health insurance and family income, were evaluated. RESULTS: By 1998, 1273 lung cancer deaths and 772 COPD deaths occurred. Lung cancer mortality rates were approximately two times higher than COPD mortality rates among race and ethnic groups. Cox regression analysis revealed that low education (RR = 1.77, significant, P = 0.01) and low family income (RR = 1.50, significant, P = 0.01) are associated with lung cancer and COPD mortality, controlling for age, race/ethnicity, sex and smoking status. CONCLUSIONS: COPD and lung cancer mortality have similar associations with health disparity indicators in the NLMS data, with some differences in the magnitude of the effect.

Resumption of postpartum luteal function of primiparous, suckled beef cows exposed continuously to bull urine.

The objective of this experiment was to determine if continuous exposure to bull urine alters resumption of ovarian cycling activity of primiparous, suckled beef cows. We tested the hypotheses that interval from urine exposure to resumption of luteal activity and proportions of cows that resume luteal activity by the end of the urine-exposure period do not differ between cows exposed to mature bull urine or steer urine. Thirty-eight Angus (A) x Hereford (H) cows, 4 mature A x H bulls and four 10-mo-old A x H steers, were used in this study. Cows were stratified by calving date, cow BW, calf BW, calf sex, dystocia score, and BCS; fitted with a controlled urine delivery device 2 wk before the start of treatments; and assigned randomly to be exposed continuously (24 h/d) to bull urine (n = 19) or steer urine (n = 19) beginning 40 d after calving. Urine was collected from bulls and steers every third day of the experiment. Blood samples were collected from cows starting on d 0 and every third day thereafter until the end of the exposure period (approximately 64 d). Likewise, controlled urine delivery devices were filled and refilled on the same schedule. Neither interval from urine exposure to resumption of luteal activity nor proportions of cows that resumed luteal activity during the urine-exposure period differed between cows exposed to bull urine or steer urine. We concluded that continuous exposure to mature bull urine does not affect resumption of luteal activity of primiparous, suckled beef cows.

A validation of the 10-meter incremental shuttle walk test as a measure of aerobic power in cardiac and rheumatoid arthritis patients.

OBJECTIVE: To validate a simple, clinically relevant, and inexpensive test of aerobic power-the 10-meter incremental shuttle walk test (SWT)--in 2 separate patient populations. DESIGN: Two-sample validity study. SETTING: Physiotherapy department of major hospital in the United Kingdom. PATIENTS: Convenience samples of rheumatoid arthritis (RA) patients (n = 10) and cardiac patients (n = 10). INTERVENTION: Subjects were attached to a portable respiratory gas analyzer to measure oxygen uptake. They walked around an oval 10-meter course, starting at 0.5m/s, with velocity gradually increased by .17m/s increments for as long as they could, for up to 12 minutes. MAIN OUTCOME MEASURES: A subject's maximal rate of oxygen uptake during exercise (V(O)(2)max) established with linear extrapolation was regressed against the number of shuttles completed (distance walked). An earlier study (n = 28) showed high levels of reliability and validity with linear extrapolation. RESULTS: No significant linear relationship was found between V(O)(2)max and the number of shuttles completed (R(2); RA subjects = 9.7%, cardiac subjects = .03%, p > .05). CONCLUSION: These results do not support use of the SWT as a representative measure of aerobic power. Despite this finding, the advantages of developing a clinically viable alternative to costly laboratory testing warrants further study of the SWT in patient groups.

Marital status and mortality: the national longitudinal mortality study.

PURPOSE: To examine the effect of marital status (married, widowed, divorced/separated, and never-married) on mortality in a cohort of 281,460 men and women, ages 45 years and older, of black and white races, who were part of the National Longitudinal Mortality Study (NLMS). METHODS: Major findings are based on assessments of estimated relative risk (RR) from Cox proportional hazards models. Duration of bereavement for the widowed is also estimated using the Cox model. RESULTS: For persons aged 45-64, each of the non-married groups generally showed statistically significant increased risk compared to their married counterparts (RR for white males, 1.24-1.39; white females, 1.46-1.49; black males, 1.27-1.57; and black females, 1. 10-1.36). Older age groups tended to have smaller RRs than their younger counterparts. Elevated risk for non-married females was comparable to that of non-married males. For cardiovascular disease mortality, widowed and never-married white males ages 45-64 showed statistically significant increased RRs of 1.25 and 1.32, respectively, whereas each non-married group of white females showed statistically significant increased RRs from 1.50 to 1.60. RRs for causes other than cardiovascular diseases or cancers were high (for white males ages 45-64: widowed, 1.85; divorced/separated, 2.15; and never-married, 1.48). The importance of labor force status in determining the elevated risk of non-married males compared to non-married females by race is shown. CONCLUSIONS: Each of the non-married categories show elevated RR of death compared to married persons, and these effects continue to be strong after adjustment for other socioeconomic factors.

Classifying reasons for hospital readmissions.

Readmissions are a key measurement tool in today's outcomes-focused health care environment. Monitoring the volume of readmissions is a straightforward process in light of the database resources available to care providers. Examining and reporting on the actual reasons for readmissions provides opportunities for improvement specific to the needs of a patient population. The readmission coding tool used at the Medical University of South Carolina demonstrates both the ability to assess the causes for patients returning to our institution within thirty days of discharge and the opportunity to correct problems in specific service areas with regard to discharge planning.

The relation of residential segregation to all-cause mortality: a study in black and white.

OBJECTIVES: This study investigated the influence of an aggregate measure of the social environment on racial differences in all-cause mortality. METHODS: Data from the National Longitudinal Mortality Study were analyzed. RESULTS: After adjustment for family income, age-adjusted mortality risk increased with increasing minority residential segregation among Blacks aged 25 to 44 years and non-Blacks aged 45 to 64 years. In most age/race/gender groups, the highest and lowest mortality risks occurred in the highest and lowest categories of residential segregation, respectively. CONCLUSIONS: These results suggest that minority residential segregation may influence mortality risk and underscore the traditional emphasis on the social underpinnings of disease and death.

Quality of death rates by race and Hispanic origin: a summary of current research, 1999.

OBJECTIVES: This report provides a summary of current knowledge and research on the quality and reliability of death rates by race and Hispanic origin in official mortality statistics of the United States produced by the National Center for Health Statistics (NCHS). It also provides a quantitative assessment of bias in death rates by race and Hispanic origin. It identifies areas for targeted research. METHODS: Death rates are based on information on deaths (numerators of the rates) from death certificates filed in the states and compiled into a national database by NCHS, and on population data (denominators) from the Census Bureau. Selected studies of race/Hispanic-origin misclassification and under coverage are summarized on deaths and population. Estimates are made of the separate and the joint bias on death rates by race and Hispanic origin from the two sources. Simplifying assumptions are made about the stability of the biases over time and among age groups. Original results are presented using an expanded and updated database from the National Longitudinal Mortality Study. RESULTS: While biases in the numerator and denominator tend to offset each other somewhat, death rates for all groups show net effects of race misclassification and under coverage. For the white population and the black population, published death rates are overstated in official publications by an estimated 1.0 percent and 5.0 percent, respectively, resulting principally from undercounts of these population groups in the census. Death rates for the other minority groups are understated in official publications approximately as follows: American Indians, 21 percent; Asian or Pacific Islanders, 11 percent; and Hispanics, 2 percent. These estimates do not take into account differential misreporting of age among the race/ethnic groups.

A comparison of the relationships of education and income with mortality: the National Longitudinal Mortality Study.

A sample of over 400,000 men and women, ages 25-64, from the National Longitudinal Mortality Study (NLMS), a cohort study representative of the noninstitutionalized US population, was followed for mortality between the years of 1979 and 1989 in order to compare and contrast the functional forms of the relationships of education and income with mortality. Results from the study suggest that functional forms for both variables are nonlinear. Education is described significantly better by a trichotomy (represented by less than a high school diploma, a high school diploma or greater but no college diploma, or a college diploma or greater) than by a simple linear function for both men (p < 0.0001 for lack of fit) and women (p = 0.006 for lack of fit). For describing the association between income and mortality, a two-sloped function, where the decrease in mortality associated with a US$1000 increase in income is much greater at incomes below US$22,500 than at incomes above US$22,500, fits significantly better than a linear function for both men (p < 0.0001 for lack of fit) and women (p = 0.0005 for lack of fit). The different shapes for the two functional forms imply that differences in mortality may primarily be a function of income at the low end of the socioeconomic continuum, but primarily a function of education at the high end.

The impact of specific occupation on mortality in the U.S. National Longitudinal Mortality Study.

We compare mortality differences for specific and general categories of occupations using a national cohort of approximately 380,000 persons aged 25-64 from the U.S. National Longitudinal Mortality Study. Based on comparisons of relative risk obtained from Cox proportional-hazards model analyses, higher risk is observed in moving across the occupational spectrum from the technical, highly skilled occupations to less-skilled and generally more labor-intensive occupations. Mortality differences obtained for social status groups of specific occupations are almost completely accounted for by adjustments for income and education. Important differences are shown to exist for selected specific occupations beyond those accounted for by social status, income, and education. High-risk specific occupations include taxi drivers, cooks, longshoremen, and transportation operatives. Low-risk specific occupations include lawyers, natural scientists, teachers, farmers, and a variety of engineers.

Behaviorally selective effects of neuroactive steroids on plus-maze anxiety in mice.

A number of A-ring-reduced metabolites of deoxycorticosterone and progesterone, known to exert agonist activity at the GABA(A) receptor complex, have been reported to reduce anxiety-related behavior in rodents. In the present study, the behavioral selectivity of these effects was assessed in an ethological version of the mouse elevated plus-maze paradigm. Anxiolytic-like profiles, characterised principally by reductions in open arm avoidance measures, were observed following systemic treatment with 5alpha-pregnan-3alpha, 21-diol-20-one (5alpha,3alpha-THDOC; 5.0 and 20.0 mg/kg), 5beta-pregnan-3,20-dione (5beta-DHP; 10-20 mg/kg), 5beta-pregnan-3alpha-ol-20-one (pregnanolone; 20 mg/kg), and 5alpha-pregnan-3alpha-ol-20-one (allopregnanolone; 10-20 mg/kg). In contrast, 5alpha-pregnan-3,20-dione (5alpha-DHP; 10.0-20.0 mg/kg) and 5alpha-pregnan-3beta-ol-20-one (2.5-20.0 mg/kg) were without effect under present test conditions. Detailed behavioral analysis further showed that the antianxiety effects of 5alpha,3alpha-THDOC, 5alpha-DHP, pregnanolone and allopregnanolone were not associated with changes in general activity levels. In addition, profile comparisons revealed that the anxiolytic steroids tend to produce a narrower range of behavioral effects than diazepam (1.0 mg/kg) and, in particular, do not reliably decrease measures of risk assessment. It is concluded that neuroactive steroids produce anxioselective effects in the mouse plus-maze and that their profile of action can at least partially be distinguished from that of a well-characterised benzodiazepine.

Resistance of experientially-induced changes in murine plus-maze behaviour to altered retest conditions.

Prior exposure to the elevated plus-maze results in profound behavioural alterations in rats and mice, with 24 h retest profiles indicative of fear sensitization. The present study was designed to examine the influence of retest cues on this phenomenon in male DBA/2 mice. Results confirmed the potent influence of prior maze experience on subsequent behavioural patterns, and showed that this was not affected by manipulations of extra-maze cues (90 degrees re-orientation of the maze or use of a different laboratory) on Trial 2. Data are discussed in relation to experientially-induced shifts in behavioural strategy and the apparent involvement of simple proximal cues (probably thigmotactic) in this enduring and adaptive form of spatial learning.

A study of the phototoxic potential of trovafloxacin in BALB/c mice.

Trovafloxacin, a broad-spectrum naphthyridone antimicrobial agent, was evaluated for potential phototoxicity in a standardized in-vivo test system that has been used previously to assess quinolone antibiotics. Fasted BALB/c mice were given a single oral dose of either trovafloxacin mesylate (10, 30, 90 or 250 mg/kg) or the positive control lomefloxacin hydrochloride (71 mg/kg) and immediately exposed to long-wave ultraviolet (UVA) light. Animals were irradiated for 4 h, equal to a total UV light irradiation of approximately 18 J/cm2. Before dosing, at the end of the irradiation period and at approximately 24, 48, 72 and 96 h after dosing, both ears of each mouse were evaluated for changes indicative of a positive response: erythema, oedema or a measurable increase in ear thickness. Under the conditions of this study, trovafloxacin produced a mild response (erythema and a slight increase in ear thickness) in mice given a dose of 90 or 250 mg/kg; no significant response was observed in mice given either lower doses (10 or 30 mg/kg) or the vehicle. In contrast, 71 mg/kg of lomefloxacin produced a strong and persistent phototoxic response. The results of this study demonstrate that the phototoxic potential of trovafloxacin is considerably less than that of lomefloxacin and, when compared with similar studies with related compounds, suggest that trovafloxacin is among the least phototoxic of the fluoroquinolone class.

Evaluation of social status as a contributing factor to the stroke belt region of the United States.

BACKGROUND AND PURPOSE: The southeastern United States has stroke mortality rates above the national average. The causes for this excess mortality are unknown; however, lower socioeconomic status (SES) is a risk factor for stroke, and the lower SES in the Southeast is a potential cause. In this report we assess the proportion of the excess stroke mortality attributable to SES. METHODS: The more than 400,000 participants in the National Longitudinal Mortality Study were categorized into three regions: the coastal plain region of North Carolina, South Carolina, and Georgia ("stroke buckle"); the remainder of these states plus five other southern states ("stroke belt"); and the remainder of the United States. The stroke mortality rates were calculated with and without adjustment for SES, and the proportion of the excess mortality attributable to SES was estimated. RESULTS: In persons between the ages of 35 and 54 years, stroke mortality in the stroke buckle is estimated to be more than twice that of the rest of the nation and 1.7 times greater for ages 55 to 74 years. For persons in the stroke belt, the stroke mortality was 1.3 times greater than that in the rest of the nation for the ages of 35 to 54 and 55 to 74 years. Less than 16% of this excess stroke morality was attributable to SES. CONCLUSIONS: SES does not appear to be a major contributor to the excess mortality in the southeastern United States. Of additional concern is the stroke buckle region, which was shown to have stroke mortality rates substantially greater than those in the traditionally recognized stroke belt.

The disappearing vagina syndrome.

We describe the case histories of five women who developed a severe ulcerating and constricting condition of the vagina following hysterectomy. Three of these women had other classic ulcerative conditions of skin, mouth or colon. One of these women has been described previously.

Validity of education information on the death certificate.

We compared education as recorded on the death certificate with education ascertained before death from a household survey of 10,423 persons age 25 years or more who died in 1989. There was a tendency for the decedent's education to be reported at a higher level on the death certificate than at baseline. Of those who were reported as high school graduates on the death certificate, 38% reported that they had less than a high school education at baseline. The bias was more pronounced in older than younger decedents.

Plus-maze retest profile in mice: importance of initial stages of trail 1 and response to post-trail cholinergic receptor blockade.

Recent research has shown that a single undrugged prior experience of the elevated plus-maze produces significant behavioural changes upon 24-h retest in rats and mice. Typically, when reexposed to the maze, animals display an increased avoidance of the open arms and a corresponding preference for the enclosed sections of the apparatus. Using ethological analyses, the present series of experiments sought to further characterize this phenomenon in mice and to determine whether or not it involves cholinergic receptor mechanisms. Results confirmed that behaviour during Trial 2 is markedly different to that seen on initial exposure, and that such changes are independent of the duration of Trial 1 (2 vs. 5 min). Retest behavioural changes included reduced entry latencies, reduced open arm entries, less time on the open arms and centre platform, lower levels of exploratory head-dipping, and increased entries into and time spent in the closed arms. The importance to the retest phenomenon of the first few minutes of initial exposure was further suggested by min-by-min analyses of the behaviour of animals naive to the maze. Results showed that behaviour during the first min is characterized by high levels of risk assessment from the centre platform and relatively low, but equal, levels of open- and closed-arm exploration. From min 2 onwards, however, behaviour showed a marked change with increasing open arm/centre platform avoidance, increasing closed-arm preference, and decreasing levels of risk assessment and exploratory head-dipping. Thus, it would appear that this within-session aversive learning transfers between sessions to account for behavioural profiles on retest. Irrespective of the duration of Trial 1 (2 or 5 min), posttrial administration of the muscarinic antagonist, scopolamine (0.1-1.0 mg/kg), failed to significantly alter the behavioural changes seen between trials. Data are discussed in relation to the apparent sensitization of fear produced by plus-maze exposure, its possible relation to phobia acquisition, and the need for further research on underlying mechanisms.

Modulation of plus-maze behaviour in mice by the preferential D3-receptor agonist 7-OH-DPAT.

Differences in the behavioural profiles of dopamine D2 receptor antagonists (e.g., haloperidol vs. sulpiride) in a animal models of anxiety have prompted speculation concerning the importance of their relative affinities for D2-like receptor populations. In an initial attempt to investigate the involvement of D3 receptors in anxiety, the present study examined the effects of the preferential D3-receptor agonist, (+/-)7-OH-DPAT (0.01-10.0 mg/kg), on behaviours displayed by male mice in the elevated plus-maze paradigm. An ethological approach incorporating measurement of a range of defensive acts and postures in addition to conventional parameters was used to provide a comprehensive behavioural profile for the compound. Data analysis indicated a significant increase in percentage of open-arm entries at 10 mg/kg and an altered temporal distribution of behaviour at 1-10 mg/kg. Furthermore, risk-assessment measures (stretched attend postures, closed-arm returns) were dose dependently reduced by drug treatment. Although these behavioural changes would be consistent with anxiety reduction, such an interpretation is negated by dose-dependent decreases in all active behaviours (arm entries, rearing, and head-dipping) and by marked increases in entry latencies and nonexploratory behaviour at the highest dose tested. Overall, these effects are remarkably similar to those previously reported for quinpirole, suggesting either that D2 and D3 receptors exert similar behavioural control or that the agents employed are sufficiently potent at D2 receptors to prevent a resolution of D2 and D3 responses.

Salvage of infected ICDs: management without removal.

During the 7-year period from August 1986 to December 1993, 242 patients with malignant ventricular arrhythmias underwent 242 ICD implantations and 50 subcutaneous generator changes. Wound infections developed in 5 patients (1.7%): in 3 cases, after primary implantation (3/242 [1.2%]); and in 2 following a generator change (2/50 [4.0%]). This difference was not statistically significant. Infection developed at the generator pocket and became clinically manifest between 6 weeks and 40 months, postoperatively. Our treatment approach with the first patient consisted of simple debridement of the pocket and reimplantation of the existing generator. This led to recurrence, and the generator was safely explanted. In the remaining four patients, our approach has been that of local treatment, with wide debridement of the pocket, and placement of a closed irrigation system with continuous irrigation with a bacitracin, polymyxin, neomycin solution, and culture-specific antibiotic therapy. We have successfully controlled the infection and salvaged the generator with this approach in all four patients, who are all alive and well at a mean follow-up of 25.0 +/- 17.3 months with no recurrence. The good results obtained in these patients suggest that the concept of total explanation of the infected ICD should be reassessed.